Space telegraphy.



No. 768,002. PATENTED AUG. 16, 1904. J. s. STONE.

SPACE TELEGRAPHY. APPLICATION FILED MAR. 25, 1904.

N0 MODEL.

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WITNESSES- h/EPFI'EIR.

11 I ghiiw glfibufi/ UNITED STATES Patented August 16, 1904.

PATENT Genres.

JOHN STONE STONE, 0F CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO WILLIAM W.SWAN, TRUSTEE, OF BROOKLINE, -MASSACHUSETTS.

SPACE TELEGRAPHY.

SPECIFICATION forming part of Letters Patent No. 768,002, dated August16-, 1904.

Original application filed November 26, 1903, Serial No. 182,627.Divided and this application filed March 25, 1904;. Serial No.

- 199,924. (No model.)

To all whom it may concern.-

Be it known that I, JOHN STONE STONE, a citizen of the United States,and a resident of Cambridge, in the county of Middlesex and State ofMassachusetts, have invented a certain new and useful Improvement inSpace Telegraphy, of which the following is a specification. v

The present invention depends upon the fact that if in a verticalconductor or conductors lying in a plane equidistant at all points fromtwo other vertical conductors there be developed electrical oscillationsthen the oscillations thereby developed in the last-named conductor orconductors will be equal in amplitude and phase. Further, if the efiectsof these oscillations upon a receiving device be opposed to one anothertheir resultant eflect upon said receiving device will be m'Z.

By my invention I utilize as a transmittingconductor a conductor orconductors lying in a plane equidistant at all points from two othervertical conductors which are utilized as receiving-conductors, and Icause the oscillations developed in the receivingconductors to beopposed to one another in their effect upon a receiving or translatingdevice associated with them. This may be done by means of a variety ofapparatus of the nature of induction-balances, some forms of which willbe hereinafter described. Careful consideration will show that the twovertical receiving-conductors will be incapable of receiving signalsfrom any transmitting-station in their equatorial plane, but will ingeneral be capable of receiving signals from stations otherwise located.In order that they may be most sensitive to the signals from distanttransmitting-stations, these two conductors should be placed at adistance apart of onehalf a Wave length and in the vertical planeincluding the distant transmitting-station to be communicated with. Ifit be desired to receive from more than one transmitting station, thetwo receiving-wires may be mounted upon a frame capable of rotationaround a central vertical axis.

In the drawings accompanying and forming a part of this specification,Figures 1 and 2 illustrate two forms of apparatus and circuitarrangements whereby the method hereinafter claimed may be carried intoeffect. My invention, however, is broader than mere apparatus and may becarried out by a variety of apparatus and circuit arrangements, whilethe particular apparatus herein described forms no part of the presentinvention, having been claimed in my application, Serial No. 182,627,filed November 25, 1903, of which this. application is a division.

In the figures, V V V are vertical conductors. G is a ground connection.M M M are induction-coils or transformers. I1 11 are the primaries, andI2 is the secondary, of the transformer M". C C C O are condensers. B isa battery. R is a resistance. T is a relay or suitable signal-indicatingdevice. T is an electromagnet with a mechanically-attuned armaturer,such as is well known in reed telegraphy, or a monotelephone2 e. atelephone responding to impulses of currentfrom the battery B of adefinite predetermined frequency only. K is a receiver or Wave-detector,which may be a coherer. D

is a self-restoring wave-detector, which may be a bolometer. L L1 areinductances. is is a key. A is an alternating-current generator or othersource of periodically-varying electrornotive force. .9 is a spark-gap.

In my Letters Patent No. 716,955, dated December 30, 1902, I havedescribed a systemfor simultaneously transmitting and receivingspace-telegraph signals identical in every respect with the systemdescribed herein except in this, that the closed circuit containing thereceiver K, associated with the differential coil M, is not described asattuned to absorb the energy of electrical oscillations of a frequencydiiferent from that of the oscillations developed by the sonorouscircuit a C M L. Reference may therefore be had to said Letters Patentfor details of apparatus and the operation thereof. Such attuning ofsaid closed circuit is not absolutely necessary; but less care need betaken in the adjustment of the primary windings of the coil M" if theperiod of the circuit associated with the receiver be different fromthat of the oscillations developed in the elevated conductors V V" byelectromagnetic waves radiated by the transmitting-conductor V, thefrequency of said waves being determined by the electromagneticconstants of the sonorous circuit 8 C M L.

The frequency to which the resonant circuit I2 C" C L1 is attuned isdetermined by the electromagnetic constants of said resonant circuit andis different from the frequency of the electrical oscillations developedby the sonorous circuit 8 C l\/ L and is therefore different from thefrequency of the waves radiated by the elevated conductor V, with whichsaid sonorous circuit is associated.

In Fig. 2 the receiver or wave-detector is diagrammatically illustratedas a bolometer, the fine wires or strips of which form a parallelogramthe sides of which are identical in every respect, so that theparallelogram constitutes a balanced \Vheatstones bridge, to theequipotential points of which the local circuit containing thesignal-indicating device is connected, thus avoiding the use ofchoking-coils, which would be necessary were a single line wire or stripemployed. Such bolometer has been described by me in my applicationSerial No. 119,211, in which I have pointed out that the thermal timeconstant, and therefore the massthat is, the length and seotion shouldbe small compared with the thermal time constant and the mass ofsomewhat similar instruments heretofore used for determining the wavelength of waves in wires. The bolometer diagrammatically illustrated inFig. 2, however, is merely illustrative or typical of any suitableself-restoring wave-detector, and in lieu thereof I may employ thereceiver described in the British patent to Brown, No. 28,955, of 1896,which consists of a metallic tripod resting upon a metallic plate. I mayalso employ the receiver, consisting of fine steel needles bridging twocarbon electrodes, which has been described in the Russian patentgranted to Alexandre Popoff, No. 6,066, June 14, 1899, and alsodescribed by said Popofl' in the Uomptes Rcndus (Ze ZAcademie desSciences, Tome 131, December 15, 1900, page 1296, and in the Rnpports(Z16 Umzgres International 0Z0 ZElectrz'cite, August 18 to 25, 1900,page 460.

The signal-indicating device in this case is an electromagnet T, havinga reed-armature r mechanically attuned to respond to a predeterminednumber of impulses of battery-current per second corresponding to thenumber of times per second the bolometer or other self-restoringwave-detector varies theflow of current from the potentiometer R throughthe windings of the magnet T. The number of times per second that thewave-detector changes its resistance corresponds to the group orwave-train frequency of the electromagnetic waves transmitted from adistant station and absorbed by the resonant circuit I2 (9 D L1; asexplained in my application Serial No. 182,629. This group or wave-trainfrequency, sometimes called spark frequency, is to be made differentfrom the group or wave-train frequency of electromagnetic wavestransmitted by the elevated conductor V at the home stationz. e.different from the number of times per second that the condenser C ischarged by the alternating-current generator A.

The operation of the system is as follows: If the electricaloscillations developed in conductors V V by electromagnetic wavestransmitted by conductor V are not completely neutralized as regards thesecondary I2 of the differential coils 11 I1, then the oscillationsdeveloped in the resonant circuit I20 C L1 or the resonant circuit 12 CD L, not being ofthe frequency to which said circuits areimade resonant,are of too small amplitude to effect the response of the receiver. As anextra precaution if the electrical oscillations developed in saidresonant circuit are of sufficient am plitude to eflect the response ofthe receiver D, which if it be a bolometer is exceedingly sensitive tocurrents of very small amplitude, notwithstanding .the fact that aresonant circuit strongly opposes the development therein of currents offrequencies different from that to which it is attuned, then by. usingthesignalindicating device T attuned mechanically to a given sparkfrequency the generation or radiation of electromagnetic waves at astation can be accomplished without effecting any response of thesignal-indicatingdevice 2'.e. ,the receiver is maintained in a conditionto receive signals from a distant transmitting-station at the same timethat signals are being transmitted from the home transmitting-station.

I claim- 1. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating electromagneticsignal-waves of a definite frequency at a station, neutralizing theeffects of such generation on an electroreceptive device at the samestation, amplifying the electrical oscillations resultin g fromelectromagnetic signal-waves received from a distanttransmitting-station by means of a resonant circuit attuned to thefrequency of said oscillations, and utilizing said oscillations toactuate said electroreceptive device and to thereby produce intelligiblesignals in a signal-indicating device.

2. The method of simultaneously transmitting and receivingspace-telegraph signals which consists: in generating electromagneticsignal-waves of definite group or wave-train frequency at a station,neutralizing the effects of such generation on an electroreceptivedevice at the same station, and utilizing the energy of electromageticsignal-waves of a different group or wave-train frequency transmittedfrom a distant station to actuate said electroreceptive device and tothereby produce intelligible signals in a signal-indicating device,mechanically attuned to the group or wave-train frequency of thelwavesthe energy of which is to be received.

3. In space telegraphy, the method herein described of preventingelectromagnetic signal-waves the energy of which is not intended to bereceived from effecting the response of a signal-indicating device,which consists in absorbing the energy of said waves by two elevatedreceiving-conductors, neutralizing the eflects of the resultingelectrical oscilla- U tions on an electroreceptive device and attun ingsaid signal-indicating device mechanically to respond to currents of apredetermined frequency different'from the group or wavetrain frequencyof said waves.

4:. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating or transmittingelectromagnetic signal-waves of a definite frequency at a station,neutralizing the effects of such generation or transmission on anelectroreceptive device at the same station, selectively receiving atsaid station the energy of electromagnetic signal-waves of a differentfrequency transmitted from a distant station, and utilizing the energyof the resulting elec trical oscillations to produce intelligiblesignals.

5. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating or transmittingelectromagnetic signalwaves of a definite frequency at a station,neutralizing the effects of such generation or transmission on anelectroreceptive device at the same station, selectively receiving atsaid station the energy of electromagnetic signal waves transmitted froma distant station, and utilizing the energy of the resulting electricaloscillations to produce intelligible signals.

6. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating or transmittingelectromagnetic signal-Waves of a definite frequency at a station,neutralizing the effects of such generation or transmission on an elec;troreceptive device at the same station, selectively receiving at saidstation the energy of electromagnetic waves transmitted from a distantstation and, utilizing the dissipativeenergy of the resulting electricaloscillations to produce intelligible signals.

7. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating electromagneticsignal-waves of definite group or wave-train frequency at a station,receiving at said .station the energy of electromagnetic signalwaves ofa different group or wave-train frequency transmitted from a distantstation, utilizing the energy of the resulting electrical oscillationsto produce current impulses correspondingin frequency to the group orwavetrain frequency of the waves received and selecting said currentimpulses to produce intelligi'ble signals.

8. Themethod of simultaneously transmitting and receivingspace-telegraph signals which-consists in generating electromagneticsignal-waves of definite group or wave-train frequency at a station,receiving at said station the energy of electromagnetic signalwaves of adifferent group or wave train frequency transmitted from a distantstation, utilizing the energy of the resulting electrical oscillationsto produce current impulses corresponding in frequency to the group orwavetrain frequency of the'waves received and utilizing. said currentimpulses to produce intelligible signals in a signal-indicating deviceadapted to respond to current impulses of said frequency to theexclusion of current impulses of other frequencies.

9. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating electromagneticsignal-waves of definite group or wave-train frequency at a station,receiving at said station the energy of electromagnetic signalwaves of adifferent group or wave-tra n frequency transmitted from a distantstation, utilizing the energy of the resulting electrical oscillationsto produce current impulses corresponding in frequency to the group orwavetrain frequency of the waves received and mechanieally selectingsaid current impulses to thereby produce intelligible signals.

10. The method of simultaneously transmitting and receivingspace-telegraph signals which consists in generating electromagneticsignal-waves of definite group or wave-train frequency at a station,selectively receiving at said station the energy of electromagneticsignal-waves of a different group or wavetrain frequency and utilizingthe energy of the resulting electrical oscillations to produceintelligible signals.

11. The method of simultaneously transmi tting and receivingspace-telegraph signals which consists in generating electromagneticsignal-Waves of definite group or wave-train frequency at a station,receiving at said station the energy of electromagnetic signalwaves of adifferent group or wave-train frequency and utilizing the energy of theresulting electrical oscillations to produce intelligible signals. a

12. The method of receiving space-telegraph signals which consists inabsorbing the energy of electromagnetic signal-waves of a definitecorresponding in frequency to the group or wave-train frequency of theWaves received and selecting said current impulses to produceintelligible signals.

13. The method of receiving space-telegraph signals which consists inabsorbing the energy of electromagnetic signal-Waves of a definitefrequency and of predetermined group or Wave-train frequency, amplifyingthe resulting electrical oscillations by means-of a resonant circuit,attuned to the frequency of said electrical oscillations, utilizing theenergy of said oscillations to produce current impulses corresponding infrequency to the group or wave-train frequency of the waves received andutilizing said current impulses to produce intelligible signals in asignal-indicatingdevice adapted to respond to current impulses of saidfrequency to the exclusion of current impulses of other frequencies.

14. The method of receiving space-telegraph signals which consists inabsorbing the energy of electromagnetic signal-Waves of a definitefrequency and of predetermined group or Wave-train frequency, amplifyingthe resulting electrical oscillations by means of a resonant circuitattuned to the frequency of said electrical oscillations, utilizing theenergy of said oscillations to produce current impulses corresponding infrequency to the group or Wave-train frequency of the Waves received andmechanically selecting said current impulses to thereby produceintelligible signals.

15. The method of receiving space-telegraph signals which consists inselectively receivingthe energy of electromagnetic signal-waves ofdefinite frequency and of predetermined group or wave-train frequency,developing by the resulting electrical oscillations current impulsescorresponding in frequency to the group or Wave-train frequency of theWaves received and selecting said current impulses to produceintelligible signals.

16. Themethod of receiving space-telegraph signals which consists inselectively receiving the energy of electromagnetic signal-waves ofdefinite frequency and of predetermined group or wave-train frequency,developing by the resulting electrical oscillations currentimpulses corresponding in frequency to the group or Wave-train frequencyof the waves received and utilizing said current impulses to produceintelligible signals in a signal-indicating device adapted to respond tocurrent impulses of said frequency to the exclusion of current impulsesof other frequencies.

17. The method of receiving space-telegraph signals which consists inselectively receiving the energy of electromagnetic signal-waves ofdefinite frequency and of predetermined group or wave-trainfrequency,developing by the resulting electrical oscillations currentimpulses corresponding in frequency to the group or wave-train frequencyof the Waves received and mechanically selecting said current impulsesto thereby produce intelligible signals.

In testimony whereof I have hereunto subscribed my name this 23d day ofMarch, 1904.

JOHN STONE STONE.

Witnesses:

ALEX. P. BRoWNE, BRAINERD T. JUDKINs.

